Lubricating oils



Patented Aug. 8;, 1939 LUBRICATIN G OILS Bernard H. Shoemaker and Clarence M. Loane,

Blond, Ind., assignors to Standard Oil Company, Chicago, lit, a corporation of Hindi-- No Drawing. Application May 19, 1937, Serial No. 143,528

This invention relates to lubricants and, in particular, to addition agents imparting to lubricants improved properties.

Our invention has particular utility in prevent-- 6 ing and/or inhibiting the corrosion of hard metal alloy bearings such as copper-lead, cadmium-nickel, and cadmium-silver bearings which, to a large extent, have replaced soft metal bear ings such as Babbitt metal in the trend toward 10 internal combustion engines having high compression ratios and having increased acceleration and increased speed characteristics. use of the hard metal bearings has created lubrication and corrosion problems, particularly in connection with highly refined oils, some of which may be very corrosive to the hard metal bearings. I

By highly refined" lubricating oils we mean viscous oils which have a minimum viscosity in the range of S. A. E. 10 oils and which have been. subjected to such refining processes such as, for example, solvent extraction, that the paraflinicity of the oil is markedly increased. It has been found that highly refined lubricating oils cause corrosion to alloy bearings of the cadmium-silver type to the extent of 5 mg/cm. and even greater when such bearings are submerged for 25 hours or less in an air agitated oil which has been preoxidized at about 340 F. for '25 to 50 hours. The

motor oils may be highly refined lubricating oils as such or mixtures of highly refined lubricating oils with less highly refined lubricating oils, or stated in another way, mixtures of corrosive oils and-non-corrosive oils, examples of the latter being lubricating oil fractions from Winkler crude or crudes of the Winkler type.

We have found that the corrosion of hard metal alloy bearings by highly refined lubricating oils can be inhibited by adding to such oils up to 2% but preferably 0.05% to 0.75% of chloralkyl phos+ phites. The term chloralkyl phosphite as used herein and in the appended claims means a mono, di or tri chloralkyl phosphite'or mixtures of all three or any two thereof. The chloralkyl phosphites have the general formula:

(monr, (wonron and (RO)P(OH)2 in which R is a chloralkyl group having up to 30 carbon atoms but preferably 3 to 6 carbon atoms in each alkyl radical. The chlorine atoms of The v Control Control-+0.25% tri beta chloropropyl phos- Examples of chloralkyl phosphites are:

Tri-chlorobutyl phosphite (ClC4H8O)aP Di-chlorobutyl phosphite (C1C4H80)2POH Mono-chlorobutyl phosphite (C1C4H80) P(OH) 2 Tri-dichlorobutyl phosphite (ClzC H'zO) 3P 'I'ri-trichlorobutyl phosphite (Cl3C4HsO)3P Tri-B chloropropyl phosphite (CH3CHC1CH2O)3P Di-B chloropropyl phosphite (CHaCHClCHzO) 2P0 H CH3 I CClO P a CH: Tri-chloropropyl phosphite dichloride ClCsHeO) 3PC12 Tri-chloroamyl phosphite (ClCsHroO) 3P Tri-chlorooctyl phosphite (ClCaH1sO)3P Tri-chlorolauryl phosphite (CIC12H24O)3P Di-chlorolauryl phosphite (C112H24O) zPOH 'Iri-chloroisopropyl phosphite oil, and the time required for the test strips to lose 5 mgs. per sq. cm. of bearing surface determined. Using tri-B-chloropropyl phosphite as the inhibitor the following results are obtained:

on I Time for 5 mg. loss 1' Less than 1 day. 9 days. phit This test demonstrates the unusual corrosion inhibiting properties of tri beta chloropropyl phosphite on hard metal alloys of the cadmiumsilver type.

A mixture of 0.25% tri-chloropropyl phosphite in a 20 S. A. E. motor oil was tested in an internal combustion engine under conditions more severe than those met with during normal operations of such engines for the purpose of testing the effectiveness of chloralkyl phosphite in actual use. The engine was operated at 2500 R. P. M. at 25 B. H. P. output with a water jacket temperature of 239 F. and an oil sump temperature of about 250 F. The engine was equipped with cadmium sq.cm.bearingsur ca Duraon of Loss in girls.

on test per bearing Hours Control (20 S. A. E. 0

l1) 2. 854 Control+0.25% trichloropropyl phosphite.

The above data show the unusual eifectiveness of the chloralkyl phosphite in preventing corrosion to hard metal alloy bearings of the cadmium-silver type in an internal combustion engine in actual operation, and check the laboratory results shown hereinbefore.

While the tri-beta. chloropropyl phosphite is very eifective as a corrosion inhibitor for hard metal bearing alloys, under some conditions it has a detrimental effect on the color stability of the oil. We have found that the color stability of the oil containing tri-beta chloropropyl phosphite may be materially improved by adding to the mixture very small amounts, for example, 0.005 to 0.75% of a butyl phosphite which is preferably a mixture of diand tri-butyl phosphite with a substantial amount but less than 3% of the mono-butyl phosphite. The addition of the mixture of butyl phosphites tooil containing tribeta chloropropyl phosphite does not affect the corrosion inhibiting properties of the latter; but does improve the color stability thereof.

While we have described our inventon by reference to a preferred embodiment thereof we do not wish to be limited to the specific example which is merely set forth to illustrae our invention and is not intended to be a limitation thereof.

We claim:

1. The method of lubricating hard metal alloy bearings having the corrosive susceptibility of alloy bearings of the group consisting of cad- .mium-silver alloys, cadmium-nickel alloys and copper-lead alloys in internal combustion engines without causing corrosion thereto which comprises applying to said bearings a lubricant comprising a mineral lubricating oil normally corrosive to said bearings and from about 0.05% to about 2% of a chloralkyl phosphite.

2. The method of lubricating hard metal alloy bearings having the corrosive susceptibility of alloy bearings of the group consisting of cadmium-silver alloys, cadmium-nickel alloys and copper-lead alloys in internalcombustion engines without causing corrosion thereto which comprises applying to said bearings a lubricant comprising a mineral lubricating oil normally corrosive to said bearings and from about 0.005% to about 2% of a chloralkyl phosphite containing up to 30 carbon atoms in the alkyl radical.

3. The method of lubricating hard metal alloy bearings having the corrosive susceptibility of alloy bearings of the group consisting of cadmium-silver alloys, cadmium-nickel alloys and copper-lead alloys in internal combustion engines without causing corrosion thereto which comprises applying to said bearings a lubricant comprising a mineral lubricating oil normally corrosive to said bearings and from about 0.05% to about 2% of a chloralkyl phosphite containing 3 to 6 carbon atoms in the alkyl radical.

4. The method of lubricating hard metal alloy bearings having the corrosive susceptibility of alloy bearings of the group consisting of cadmium-silver alloys, cadmium-nickel alloys and copper-lead alloys in internal combustion engines without causing corrosion thereto which comprises applying to said bearings a lubricant comprising a mineral lubricating oil normally corrosive to said bearings and 0.25% to 0.75% of tri-B chloropropyl phosphite.

5. The method of lubricating hard metal alloy bearings having the corrosive susceptibility of alloy bearings of the group consisting of. cadmium-silver alloys, cadmium-nickel alloys and copper-lead alloys in internal combustion engines without causing corrosion thereto which comprises applying to said bearings a lubricant comprising a. mineral lubricating oil normally corrosive to said bearings and 0.25% to 0.75% of tri-B chloropropyl phosphite and 0.5% to 0.25% of tributyl phosphite.

6. An improved motor oil non-corrosive to hard metal alloy bearings having the corrosive susceptibility of alloy bearings of the group consisting of cadmium-silver alloys, cadmium-nickel alloys and copper-lead alloys which comprises a mineral lubricating oil normally corrosive to said hard metal alloy bearings and tri-beta chloropropyl phosphite in small but sufiicient quantities to inhibit the corrosive eifect of said mineral lubricating oil.

BERNARD H. SHOEMAKER. CLARENCE M. LOANE.

CERTIFICATE OF CORRECTION. Patent No. 2,169,185. August 8, 1959.

BERNARD H. SHOEHAKER, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, second column, line 16, in the formula, before "C105" insert a parenthesis; line 19, for "(C1 H O) POH" read (CIC H M POH; page 2, first column,

line 58, for "illustrae" read illustrate; and second column, line 6, claim 2, for 90.00595" read 0.05%; and thatthe said Letters Patent shouldbecread with this correction therein that the same may conform to the record of the case in the Patent Office., I

Signed and sealed this 19th day of September, A, D. 1959.

Henry Van Arsdele, Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 2,169,185. August 8, 1959.

BERNARD H. SHOEHAKER, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, sec- 0nd column, line 16, in the formula, before "0163" insert a parenthesis; line 19, for "(C1 H O) POH" read (ClC H O) POH; page 2, first column, line 58, for "illustrae" read illustrate; and second column, line 6, claim 2, for "0.005%" read 0.05%; and that the said Letters Patent should beread with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 19th day of September, A. D. 1959.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents. 

